Polar Latitude Unsupported
polar_latitude_unsupported422
Calculations can't be performed at this latitude. Use a nearby non-polar location, or choose a different house system.
What this means
The latitude in the request falls within the Arctic or Antarctic Circle (above ~66.5° or below ~−66.5°), where standard astrological calculations either fail or produce undefined results. On certain dates, the Sun doesn't rise or set at all (polar day or polar night), and the Placidus and Koch house systems break down mathematically near the poles. We refuse rather than return nonsense numbers.
When you'll see this
- A birth latitude is set to a polar location (a research base, an Arctic village, etc.).
- A test or fixture used an extreme latitude like 89° or −85°.
- A typo in the coordinate flipped sign or order (e.g. latitude/longitude swapped).
- A geocoder returned polar coordinates for a misinterpreted location query.
Learn more about how this works
The Earth's rotation, the Sun's apparent path, and the celestial sphere all behave in ways at the poles that violate the assumptions of equal-time-arc house systems. Placidus and Koch in particular use a daily arc of the Sun that doesn't exist on polar-day or polar-night dates. Equal house and whole-sign systems are immune to this — they only need the Ascendant longitude, which is computable even at high latitudes (with reduced precision, but no breakdown).
The most common gotcha: if you genuinely need to compute a chart for someone born in a polar latitude, switching to the equal or whole_sign house system usually works. The error fires only when the requested system can't produce a result.
Example response
{
"success": false,
"error": "polar_latitude_unsupported",
"message": "Calculations cannot be performed at this latitude. Locations within the polar circles may not have a computable sunrise, sunset, or houses on this date. Use a nearby non-polar location, or a different date.",
"details": [],
"retry_after": null,
"doc_url": "https://docs.asterwise.com/reference/errors/polar_latitude_unsupported",
"request_id": "req_01HXYZABCDEFGH",
"timestamp": "2026-05-25T12:34:56Z"
}
- Verify the latitude in the request matches the intended location. Most occurrences are typos or coordinate swaps.
- If the location is genuinely polar (research station, etc.), switch to the
equalorwhole_signhouse system, which doesn't have polar singularities. - For brief polar visits or expeditions, use the person's habitual non-polar latitude instead — most astrological traditions treat the actual location loosely for unusual cases.
Pre-validate latitude on your side; offer the user a fallback house system if their birth location is polar.
Python:
Production handler
- Python
- TypeScript
import httpx
def call_asterwise(url, headers, payload):
lat = payload["birth"]["lat"]
if abs(lat) > 66.5 and payload["birth"].get("house_system") in (None, "placidus", "koch"):
# Suggest equal-house fallback
payload["birth"]["house_system"] = "equal"
response = httpx.post(url, headers=headers, json=payload, timeout=30)
response.raise_for_status()
return response.json()
async function callAsterwise(url: string, headers: HeadersInit, payload: any) {
const lat = payload.birth?.lat;
const system = payload.birth?.house_system;
if (Math.abs(lat) > 66.5 && (!system || system === "placidus" || system === "koch")) {
payload.birth.house_system = "equal";
}
const response = await fetch(url, {
method: "POST",
headers,
body: JSON.stringify(payload),
});
if (!response.ok) throw new Error(`HTTP ${response.status}`);
return response.json();
}
Avoid this error by
- For users entering custom coordinates, validate latitude range client-side and warn if it exceeds 66.5°.
- Default to
equalorwhole_signhouse systems for products targeting global users — they work everywhere, including polar regions. - Check for swapped latitude/longitude before submission. A latitude of 72 might actually be a longitude that got into the wrong field.
- Don't assume polar locations are user errors — there are real users at research stations and Arctic communities.